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The Nano Powders for Preparing Special Ceramics

Special ceramics refer to ceramic materials with special properties and specific applications. Compared with traditional ceramics, special ceramics have higher hardness, wear resistance, high temperature resistance, corrosion resistance, and insulation performance, and are widely used in various fields, including aerospace, electronics, medical, energy, chemical, etc.

 

Nano powder can play an important role in the preparation of special ceramics. By adding nano powders to the raw materials of special ceramics, the microstructure control and performance optimization of materials can be achieved. Nano powder has large specific surface area and size effect, which can enhance the mechanical properties, thermal conductivity, optical properties of special ceramics, and improve the processing properties and density of materials.

 

The following are several nano powders commonly used to prepare special ceramics:

 

Nano zirconia powder (HW-U702): With excellent mechanical properties, wear resistance, and chemical stability, it is suitable for preparing wear-resistant and corrosion-resistant special ceramics, such as cutting tools and ceramic coatings.

 

Nano alumina powder (HW-N611): With high hardness, heat resistance, and chemical stability, it can be used to prepare high-temperature ceramic materials, such as ceramic aviation engine components and high-temperature resistant electronic devices.

 

Nano tin oxide powder (HW-X678): With good conductivity and optical properties, it can be used to prepare transparent conductive ceramic materials, such as touch screens, displays, and solar cells.

 

Nano tungsten oxide powder (HW-W691): With high density, high melting point, and excellent wear resistance, it is suitable for preparing high-temperature and wear-resistant ceramic materials, such as cutting tools, bearings, and valve guides.

 

These special ceramic materials have extensive applications in many fields, including electronics, medical, aerospace, energy, and automotive industries. Their unique performance makes them suitable for various extreme environments and applications that require high durability.

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About Platinum-Carbon Catalyst and Its Application

Introduction

 

Platinum-carbon catalyst, also called Pt/C, is a carrier catalyst loaded with platinum onto activated carbon and belongs to one of the subcategories of precious metal catalysts. It is mainly used for chemical reactions such as hydrogen oxidation, methanol oxidation, formic acid oxidation and oxygen reduction in fuel cells, and is a very common precious metal catalyst. Platinum carbon catalysts have a high technological threshold and are mainly produced through three major processes: precipitation conversion, chemical reduction and alternate microwave heating, which are highly demanding. Chemical reduction is the most commonly used method for the production of platinum carbon catalysts, which refers to the use of activated carbon, distilled water and hexachloroplatinic acid solution as raw materials to generate platinum carbon catalysts through mixing and dissolving, ultrasonic shaking and chemical reduction treatment. (nano platinum powders)

 

Application

 

PEM electrolytic water cathode

Platinum-carbon catalyst is widely applied in PEM electrolytic water cathode, which is a method of decomposing water into hydrogen and oxygen. PEM electrolytic water cathode is one of the most widely used water decomposition technologies and is highly efficient, controllable and safe. With PEM electrolysis, hydrogen can be produced wherever it is needed and no emissions are produced. In the electrolytic water reaction, a platinum carbon catalyst facilitates the decomposition of water to produce hydrogen and oxygen. This process requires a lot of energy to carry out, so Pt/C catalyst can accelerate the reaction rate at low voltages. This means that using Pt/C catalyst can significantly reduce the amount of energy required to produce hydrogen and increase the efficiency of the reaction. Since the PEM electrolytic water hydrogen production equipment has made remarkable breakthroughs in technology and market, many PEM electrolyzer material companies started to enter the market one after another to start the attempt of localization and replacement.

 

Hydrogen fuel cell anode

Nowadays, new energy vehicle is the main application area for Pt/C catalyst. In this field, Pt/C catalyst plays an important role in hydrogen fuel cell anodes, as it can facilitate the reaction between hydrogen and oxygen to generate electrical energy, thus providing power for new energy vehicles. Normally, new energy vehicles use PEM fuel cells. The anode of this fuel cell requires Pt/C catalyst to accelerate the oxidation reaction of hydrogen to produce electric current. A fuel cell is an energy conversion device that converts chemical energy into electrical energy, and the electrode catalyst is one of its key raw materials. In a hydrogen fuel cell, a platinum-carbon catalyst is used to facilitate the reaction between oxygen and hydrogen. As the hydrogen passes through the electrolyte membrane into the cathode, Pt/C catalyst breaks the hydrogen into protons and electrons. The electrons flow through the circuit to produce electricity, while the protons pass through the electrolyte membrane to the anode where they combine with oxygen to form water. This process generates electricity and water for the hydrogen fuel cell.

 

Unlike conventional chemical platinum-carbon catalyst, which is loaded with less than 5%, the Pt/C catalyst for hydrogen fuel cells generally has a platinum loading of more than 20% and is very difficult to produce. Pt/C catalysts for hydrogen fuel cells require platinum nanoparticles with a particle size of 3-5nm, narrow particle size distribution, uniform dispersion on carbon, and no harmful impurities. Since the surface energy of 3-5nm Pt nanoparticles is very large and easily agglomerated, it is very difficult to prepare such a kind of Pt/C catalyst. With the development of new technologies, engineers are proactively researching to improve the structure and composition of catalysts in order to reduce their cost and increase their efficiency.

 

Pt/C catalyst is one of the fuel cell electrode catalysts commercially available in China, and the market demand for platinum carbon catalysts continues to increase, driven by the rapid growth of hydrogen fuel cell vehicle sales. According to the relevant data, the production and sales of hydrogen fuel cell vehicles in China in 2022 completed 3,626 and 3,367 units respectively, representing a year-on-year growth of 105.4% and 112.8%. In the future, with the production and sales scale of hydrogen fuel cell vehicles maintaining rapid growth, it is expected that the platinum carbon catalyst market in China will maintain growth at a CAGR of over 7% from 2023 to 2028, with promising prospects for the industry development.

 

The successful application of platinum carbon catalysts in hydrogen fuel cells and electrolytic water reactions provides a new direction for the development and utilization of clean energy. Compared with traditional fossil fuels, hydrogen has a wide range of applications as a clean energy source, and the use of Pt/C catalyst will become more common and mature.

 

Conclusion

Overall, Pt/C catalyst has a wide range of uses in hydrogen fuel cell and electrolytic water reactions, enabling much higher reaction efficiency and lower energy consumption required for the reaction. As technology and materials continue to advance, it is believed that the use of platinum carbon catalysts will become more and more widespread and offer more possibilities for the development of our clean energy.

 

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Ferroferric Oxide Nanopowder Used for Ceramic Tile Substrate

Ferroferric oxide (Fe304 HW-P632) is an important type of iron oxide material with extensive applications in magnetic materials, polymer materials, electronic materials, and other fields. In recent years, ferric oxide has gradually been introduced into ceramic tile substrates, becoming a new type of functional ceramic material.

 

Ceramic tile is a common building decoration material, and its surface quality directly affects the decoration effect and service life. At present, traditional ceramic tile surface treatment methods are mainly chemical coating or physical treatment, but these methods have disadvantages such as high cost, long treatment time, and serious environmental pollution. By adding ferroferric oxide material to the ceramic tile substrate, the performance and quality of the tiles can be easily improved, becoming a new type of ceramic material with practical application value.

 

Firstly, Fe3O4 has conductivity property, which can form a certain electrostatic field on the surface of ceramic tiles, making it easier for particles such as dirt and dust attached to the surface of tiles to be adsorbed, thus purifying the air. Secondly, it also has strong antibacterial property, which can kill surface bacteria, reduce the growth of bacteria, and thus improve the hygiene level of ceramic tile surfaces. In addition, it has photocatalytic function, which can decompose organic substances on the surface of ceramic tiles through ultraviolet light irradiation, achieving the effect of purifying air and deodorizing.

 

Research has shown that adding different proportions of Fe3O4 materials to ceramic tile substrates can maintain their basic physical and mechanical properties, while enhancing their conductivity, antibacterial properties, and photocatalytic properties. Therefore, the introduction of ferroferric oxide material into the ceramic tile substrate can not only add new performance and value into the traditional building decoration materials, but also meet the people’s demand for healthy and comfortable indoor environment. It is a new application with broad development prospects.

 

Although ferroferric oxide has been widely applied and studied, its application in ceramic tile substrates still needs further improvement in order to achieve more ideal results in practical applications. Therefore, the future research work needs to strengthen the preparation and application technology of Fe3O4 material and improve its application effect and reliability in ceramic tile substrate to meet people’s demand for high-quality indoor environment.

 

Hongwu Nano is a professional manufacturer of nano precious metal powders and their oxides, with reliable and stable product quality and excellent price. Hongwu Nano supplies Fe3O4 nanopowder. Welcome to contact us for further info. https://www.hwnanomaterial.com

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Polishing and Grinding Properties of Nano Silicon Carbide

Silicon carbide (HW-D507) is produced by smelting quartz sand, petroleum coke (or coal coke), and wood chips as raw materials through high temperature in resistance furnaces. Silicon carbide also exists in nature as a rare mineral— named as moissanite. In high technology refractory raw materials such as C, N, B and other non-oxide , silicon carbide is the most widely used and the most economical one.

 

β-SiC powder has properties such as high chemical stability, high hardness, high thermal conductivity, low thermal expansion coefficient and so on. Therefore, it has excellent performances such as anti-abrasion, high temperature resistance and thermal shock resistance. Silicon carbide can be made into abrasive powders or grinding heads for high-precision grinding and polishing of materials such as metals, ceramics, glass and plastics. Compared with traditional abrasive materials, SiC has high wear resistance, hardness and thermal stability, which can effectively improve processing accuracy and efficiency. In addition, it has excellent chemical resistance and high-temperature stability, so it has a wide range of application prospects in various fields.

 

SiC can be used to prepare polishing materials, which has a wide range of applications in mechanical engineering, electronic devices, optical devices and other fields. This polishing material has excellent properties such as high hardness, high wear resistance and high chemical stability, which can accomplish high quality polishing and grinding operations. At present, the main grinding and polishing materials is diamond in the market, and its price is tens or even hundreds of times of β-Sic. However, the grinding effect of β-Sic in many fields is no less than diamond. Compared with other abrasives of the same particle size, β-Sic has the highest processing efficiency and cost performance.

 

As polishing and grinding material, nano silicon carbide also has excellent low friction coefficient and excellent optical properties, which are widely used in microelectronic processing and optoelectronic device manufacturing. Nano silicon carbide polishing and grinding materials can achieve extremely high polishing capabilities, while controlling and reducing surface roughness and morphology, improving the surface quality of the material and the performance of the product.

 

In resin-based diamond tools, nano silicon carbide is an important additive that can effectively improve the wear resistance, cutting and polishing performance of resin-based diamond tools. Meanwhile, the small size and good dispersion of SiC can improve the processing performance of resin-based diamond tools by mixing well with resin-based materials. The process of nano SiC for manufacturing resin-based diamond tools is simple and easy. Firstly, nano SiC powder is mixed with resin powder in a predetermined ratio, and then heated and pressed through a mold, which can effectively eliminate the uneven distribution of diamond particles by using the uniform dispersion property of SiC nanoparticles, thus significantly improving the strength and hardness of the tools and extending their service life.

In addition to the manufacture of resin-based diamond tools, silicon carbide nanoparticles can also be used in manufacturing various abrasives and processing tools, such as grinding wheels, sandpaper, polishing materials, etc. The application prospect of nano silicon carbide is very broad. With the increasing tendency of various industries to use high performance and high quality processing tools and abrasives, nano silicon carbide will certainly produce more and more extensive applications in these fields.

In conclusion, nano silicon carbide powder has a wide application prospect as a high quality polishing material. With the continuous progress of science and technology, nano silicon carbide and resin-based diamond tools will be continuously improved and upgraded to a wider range of fields.

 

Hwnanomaterial is a professional manufacturer of nano precious metal powders and their oxides, with reliable and stable product quality and excellent price. Hongwu Nano supplies SiC nanopowder. Welcome to contact us for further info.

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The Importance of Nano ZrO2 on New Energy Hydrogen Production

Hydrogen energy is a kind of secondary energy with rich sources, green, low-carbon and wide application. It can help the large-scale consumption of renewable energy, realize large-scale peak regulation and cross-seasonal and cross-regional energy storage, and accelerate the low-carbon development in industry, construction, transportation and other fields.In 1970s, as an alternative energy source, hydrogen energy attracted people’s attention. At that time, the Middle East War triggered the global oil crisis. In order to get rid of the dependence on imported oil, the United States put forward the concept of “hydrogen economy” for the first time, believing that hydrogen could replace oil as the main energy source to support global transportation in the future. In the following decades, hydrogen energy has been developing. So far, the countries taking up 75% of the global economy have introduced hydrogen energy development policies to actively promote the development of hydrogen energy. Among various hydrogen production materials, nano ZrO2（HW-U702） has attracted the attention of scientists.

 

Nano ZrO2 has large specific surface area, high chemical inertness and catalytic activity, which makes ZrO2 Zirconium Oxide Nanopowder an ideal new energy catalyst for hydrogen production. First, nano ZrO2 promotes the decomposition reaction of water molecules by increasing the decomposition potential of water, producing hydrogen and oxygen. Secondly, nano ZrO2 can effectively inhibit the oxidation reaction in the process of hydrogen production, thus improving the production of hydrogen and the purity of the product.

 

Experiment data shows that nano ZrO2 catalyst can achieve efficient water decomposition reaction under mild conditions and produce high purity hydrogen gas. In addition, due to the abundant hydroxyl groups and oxygen vacancies on the surface of nano ZrO2, these functional groups will adsorb water molecules and decompose them into hydrogen and oxygen, and reduce the byproduct generation in the reaction.

 

The stability and lifetime of the nano ZrO2 catalysts are also of concern. Compared with traditional precious metal catalysts, nano ZrO2 catalyst is more stable and have a longer life. At the same time, the preparation cost of nano ZrO2 catalyst is lower, and the performance can be improved by adjusting the structure and form of nano ZrO2 catalyst, so as to further improve its application in new energy hydrogen production.

 

In general, nano ZrO2 has a wide application prospect in the field of new energy hydrogen production. With the increasing demand for hydrogen energy, we believe that nano ZrO2 catalysts will make greater progress in the future.

 

Hwnanomaterial is a professional manufacturer of nano precious metal powders and their oxides, with reliable and stable product quality and excellent price. Hongwu Nano supplies ZrO2 nanopowder. Welcome to contact us for further information.

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Introduction of gas sensing materials and application of nano tin oxide for gas sensors

A gas-sensitive material is a material that is very sensitive to a certain gas in a certain environment, generally a certain type of metal oxide, which is semiconductive by doping or non-stoichiometric changes, and its resistance changes with the changing atmosphere. Different types of gas-sensitive materials are particularly sensitive to one or several gases, and their resistance will change regularly with the concentration (partial pressure) of the gas, and their detection sensitivity is in the order of one millionth, while some individuals can reach the order of one billionth, far exceeding the olfactory perception of animals, so known as “electronic nose”.

 

A sensor is a detection device that can sense the measured information, and can transform the sensed information into electrical signals or other required forms of information output according to certain rules, so as to meet the requirements of information transmission, processing, storage, display, recorde and control requirements. A gas sensor is a sensor that senses the physicochemical properties of specific components contained in a gas and converts it into an appropriate electrical signal to detect the type and concentration of the gas. Semiconductor metal oxides such as SnO2, ZnO, Fe2O3 have been widely used as gas-sensing materials, and In2O3 as a new gas-sensing material has also attracted the attention of researchers.

 

With the continuous development of science and technology,  SnO2 Tin Oxide Nanopowder, as a special and important industrial raw material with various uses, has been continuously expanded in its use and dosage. The application of materials, etc. has shown the actual and potential huge market as gas sensitive, light, white conductive, nano composite photocatalytic materials, etc. Therefore, it is of great significance to find a preparation method with simple process equipment, low cost, high product yield and stable performance.

 

Nano tin dioxide SnO2 is the earliest and most widely used gas-sensing material. Because tin oxide nano has high gas-sensitivity to various combustible gases, it is widely used in the detection and alarm of combustible gases. The combustible gas sensor designed and manufactured with it has the characteristics of high sensitivity, large output signal, high impedance to toxic gas, long life and low cost. Taking nano tin oxide as the matrix material and incorporating appropriate catalysts or additives, a tin oxide gas sensor with selective sensitivity to alcohol, hydrogen, hydrogen sulfide, carbon monoxide and methane can also be prepared.

 

Since the gas-sensing mechanism of tin oxide is surface-controlled, the gas sensitivity is related to the specific surface area of ​​the material. Generally, the larger the specific surface area, the higher the gas sensitivity. Therefore, nanometerization and thin filmization of tin oxide gas-sensitive materials have become two ways to improve the sensitivity ratio of tin oxide gas.

 

In recent years, many materials science and electronics workers have joined this field one after another, dedicated to the research on the adsorption characteristics and detection mechanism of SnO2 gas-sensitive materials, and their products have also penetrated into various fields of petrochemical industry and household civil use. Used as a gas sensor, tin dioxide has many properties superior to other materials, such as higher sensitivity and lower operating temperature. In the past, there have been many studies on sintered and membrane sensors, which are currently widely used for the detection of toxic gases and flammable gases. However, this kind of gas sensor has poor stability and selectivity, long response time and recovery time, unsatisfactory repeatability of the device, and is not conducive to integration and multi-functionality. Nanotechnology can be used to make a large surface area thin-film and powder sensors are used to miniaturize and integrate components, improve sensitivity, and shorten response and recovery time. On the other hand, the development of highly selective sensors requires the use of silicon-based microelectronics technology, and thin-film technology is the most suitable method to achieve this goal. Another method to modify the traditional gas sensor is to dope pure tin oxide with various elements and compounds to reduce the working temperature and improve the sensitivity and selectivity.

 

Currently, Hongwu Nano has successfully produced more fine-grained nanometer tin dioxide, of which size reach to 10nm, in good shape, narrow distribution.https://www.hwnanomaterial.com

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Application of Nano Inorganic Materials in Printing Ink

The printing industry is an important part of our country’s national economy, and vigorously developing printing technology is the current development trend of the international printing industry. The application of nano materials in ink, paper and printing machine can improve the performance of printing materials, the defects of printing materials, and bring new vitality to the development of printing industry.

 

Ink fineness is closely related to the quality of printed matter. The finer the ink is, the stronger the tinting strength, and the clearer and fuller the dots of the printed matter. Nano inks undoubtedly have special advantages in terms of fineness, because nanomaterials are the materials with the finest grains at present. The nanoparticles themselves have good surface wettability, they are adsorbed on the surface of the pigment particles in the ink, which significantly improves the lipophilicity and wettability of the ink, which can better improve the printing suitability of the ink. The so-called nano particles refer to metal-based particles, oxide particles thereof, and non-metallic-based particles. The composition and characteristics of the nanopowders are different, and the characteristics of the ink made are also different. Nano metal particles can absorb all light of various wavelengths, and they appear black, but have a scattering effect on light. Therefore, the ink added with metal nano powders has higher purity and density. This is a process effect that cannot be achieved by adding ordinary materials. This is the basic law of actual performance. Using novel technology to add nano particles in resins, pigments, fillers, etc. can also achieve the effect of reducing the amount of pigment without reducing the covering power of the ink. If it is added to the UV ink, it can also speed up its curing speed and effectively avoid the shrinkage and wrinkling of the ink film.

 

Adhesion of nano inks to substrates

Nano anti-counterfeiting ink, a researcher from Beijing University of Chemical Technology compounded a material mixed with nano zirconia (ZrO2) and rare earth elements in a conventional ink binder to prepare an ink for printing anti-counterfeiting labels. After the ink is printed on the substrate, the pattern appears in one color under visible light and another under infrared light, which can achieve anti-counterfeiting purposes. There is also a magnetic anti-counterfeiting ink, which is to add nano magnetic substances to the ink, and the pictures and texts printed with this ink can detect magnetic signals under a special detector.

 

Adding nano SiO2 and nano TiO2 to the ink, because these two substances have strong anti-ultraviolet and catalytic properties, the light fastness of the synthesized nano ink is improved by 2-3 grades, and the heat resistance and adhesion are improved to some extent.

 

Conductive ink is made by adding silver nano conductive powder into the ink. This ink can be printed on ceramics and metals, and can also be used for circuit layer printing of modern touch panel switches. It has good performance and smooth and uniform film.

 

Using the ink with addition of nano TiO2 for printing on the surface of metal, plastic and other substrates can produce visual flash effect, color transfer effect, additional color effect, etc., also can make the surface color of the printed matter change richly and play a decorative effect as nano TiO2 can continuously emit visible light and produce different visual effects.

 

There are also some specific nanoscale materials that can achieve some specific effects if added to the ink. Nano inorganic materials such as nano Al203 has good fluidity, and if added to the ink, the wear resistance can be greatly improved. When some substances are at the nano scale, the particle size is different so is the color. Thus the manufacture of color ink may no longer rely on chemical pigments, but select different nano size particles of appropriate volume to present different colors.

 

Times are advancing, and new demands will always require the market to provide new products. The emergence of nano-printing technology marks that our country has reached the international forefront in the field of printing, opened up a new way of green, environmentally friendly and efficient printing, and promoted the development of my country’s printing industry in the direction of “green, functional, three-dimensional, and device-based” and it will also spawn more strategic emerging industries.

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Antibacterial Mechanism of Nano Silver Powder–Most Cost-Effective Antibacterial Material

In nature, harmful bacteria, fungi, viruses and other microorganisms are widely distributed, and they grow, multiply or mutate under certain conditions, which are the main reasons for human infections and diseases. Therefore, the development and application of antibacterial materials and antibacterial products have attracted attention from all over the world. Compared with organic antibacterial agents, inorganic antibacterial agents have the characteristics of high safety, good heat resistance and antibacterial durability; in addition, with the in-depth research of nanotechnology, nanoparticles and nanomaterials have become one of the research hotspots in the field of materials science. , Studies have shown that the antibacterial performance will be greatly enhanced after the nanometerization of the antibacterial agent. Therefore, nano-scale inorganic antibacterial agents have a lot of room for development.

 

Compared with ordinary silver powder, nano-silver power has the unique surface effect, volume effect, quantum size effect and macro-quantum tunneling effect of nano-materials. It has a strong inhibitory and killing effect on dozens of pathogenic microorganisms such as Escherichia coli, Neisseria gonorrhoeae, Chlamydia trachomatis, and will not produce drug resistance. Animal experiments show that even if the amount of this nano-silver antibacterial powder reaches several thousand times the standard dose, the tested animals have no signs of poisoning. At the same time, it also promotes the repair of damaged epithelial cells. It is worth mentioning that the antibacterial effect of this product when exposed to water is increasingly enhanced, which is more conducive to the treatment of diseases.

 

The main application areas of nano silver antibacterial include environmental protection, textiles and clothing, fruit preservation, food hygiene, fibers (fabrics, finished products), information industry, ecological environment, daily necessities, etc. Its detailed applications: cotton, linen, silk, polyester, acrylic, spandex, viscose fiber, protein fiber, finished fabrics, clothing, bedding, daily textiles, toys, etc., aquaculture, gardening facilities, soil improvement, building materials, Decorative materials, detergents, glassware, packaging paper products, paper for special industries, deodorants, antibacterial gels for external use in medicine, and plastic products.

 

Antibacterial mechanism of inorganic nano silver antibacterial agent

The biggest difference between nano-silver inorganic antibacterial agents and organic antibacterial agents is that the use of organic antibacterial agents can easily make bacteria resistant, and improper use can cause harm to the human body, while the use of nano-silver inorganic antibacterial agents will not cause bacteria at any time Produce drug resistance and have antibacterial durability. The antibacterial mechanism generally has the following aspects:

 

  1. The effective ingredients in antibacterial fibers act on cell membrane proteins. It can directly destroy the bacterial cell membrane and cause the cell contents to ooze out. Nano silver and organic antibacterial agents are adsorbed on the cell membrane, hindering bacteria and other microorganisms from absorbing amino acids, uracil and other nutrients necessary for growth, thereby inhibiting their growth.
  2. The far infrared rays emitted from the surface of the antibacterial fabric have a certain wavelength range, which can inhibit the activity of bacteria and cause the death of bacteria.
  3. The surface catalysis of nano-silver affects the normal metabolism and reproduction of bacteria, leading to the death of bacteria.

 

Anti-microbial category

1) Common pathogenic bacteria: Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Salmonella, etc.

2) Common pathogenic fungi: pathogenic molds such as Aspergillus flavus, Aspergillus nidulans, Penicillium citrinum, etc.; yeasts such as Candida albicans, etc.

3) Common molds that pollute the environment: Aspergillus niger, Aureobasidium pullulans, Paecilomyces variabilis and Trichoderma viride, etc. https://www.hwnanomaterial.com

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Nanomaterials in rubber industry application

The development of the rubber industry is closely related to the use of nanomaterials. Rubber materials in the 21st century are developing towards high performance and functionalization. Usually, the composite obtained by adding nano powder into the rubber matrix is nano-rubber. The application direction of nano-materials in rubber can be summarized as two aspects: improving mechanical properties and providing some special functions (such as anti-aging, gas barrier and antibacterial).

The common nano powders used for rubber reinforcement and more special functions are mainly oxides nanoparticles, including zinc oxide nanoparticles, alumina nanoparticles, titanium dioxide nanoparticles and silica nanoparticles. Also there are other nanomaterials such as carbon nanotubes, silicon nitride nanoparticles, nano graphene, nano diamond, etc.

 

  1. The reinforcing effect of nanomaterials on rubber

The most used and most common reinforcing agent is nano sized silica (SiO2 nanoparticles). The application results of SiO2 in tire production are more reflected in the substantial improvement of the basic performance of tires.

Multi-walled carbon nanotubes (MWCNTs) can greatly improve the mechanical properties of composite materials due to their ultra-high strength, great toughness, and unique electrical and thermal conductivity. It is much better than carbon black in terms of wear and abrasion performance, which is beneficial to the development of low-rolling tire tread compounds.

 

  1. Nanomaterials can improve the vulcanization activity of rubber

Zinc oxide (ZnO) is an essential additive in the rubber and tire industries, and can be used as a vulcanization activator and reinforcing agent for natural rubber, synthetic rubber and latex, as well as a colorant. When nano zinc oxide is used as a vulcanization activator, compared with ordinary zinc oxide, the dosage can be greatly reduced. In the formulation of rubber shoes, active nano zinc oxide is an excellent inorganic active agent and vulcanization accelerator, which can significantly improve the performance of rubber shoes and prolong its service life. In addition, it can also be used as a sterilant, which can effectively inhibit the reproduction of bacteria. It is also a good UV shielding agent and anti-aging.

 

  1. Nanomaterials can improve the heat resistance of rubber

Nano silicon nitride (Si3N4) is a gray-white high-melting-point crystalline powder, which is a covalent bond compound, and the combination is very stable. It has high chemical stability, high temperature resistance and good wear resistance. Evenly dispersing it into the rubber matrix can significantly improve the service life of heat-resistant rubber products under dynamic conditions.

 

  1. Nanomaterials can be used to produce special thermally conductive tires

Graphene conductive tires can not only meet the high performance requirements of ordinary cars, but also can be widely used in inflammable and explosive goods transport vehicles, special vehicles for electronic equipment, special vehicles for military and police, etc.

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Modification of Epoxy Resin by Silicon Carbide Whiskers (SiC-W)

Because of the small diameter, large aspect ratio, high strength, high modulus and excellent heat resistance, silicon carbide whiskers play a unique role in the modification of polymer materials. Epoxy resin has been widely used in various fields of the national economy because of its high strength, good adhesion, good thermal stability, high strength, and small shrinkage. SiC whisker modified epoxy resin can further improve its mechanical properties (strengthening and toughening), friction and wear resistance and antistatic properties.

 

Epoxy resin (EP) is one of the most widely used thermosetting polymer materials. It has excellent adhesion, thermal stability, electrical insulation, chemical resistance, high strength, small shrinkage, and low price and it’s widely used in various fields such as coatings, adhesives, light industry, construction, machinery, aerospace, electronic and electrical insulation materials, and advanced composite materials. However, due to the shortcomings of epoxy resin cured products such as high brittleness, low impact strength, easy cracking, and poor antistatic performance, its further applications are limited.

 

Epoxy resin glue is prepared by epoxy resin plus curing agent, filler and so on. It has the characteristics of high bonding strength, high hardness, good rigidity, acid, alkali, oil and organic solution resistance, and small curing shrinkage. At present, the bonding strength of epoxy adhesive is relatively high, but there are still some deficiencies in the bonding of some high-strength structures, and the bonding strength needs to be further improved.

 

Whiskers are fibers with extremely small diameters grown in the form of single crystals under special conditions. They have a highly ordered atomic arrangement structure, so they can approach the theoretical strength of valence bonds between atoms, and have great potential for strengthening epoxy adhesives. Many research results show that filling whiskers into epoxy resin matrix can effectively solve these shortcomings and greatly improve the comprehensive performance of epoxy resin.

 

Silicon carbide whisker is a cubic whisker whose crystal form is the same as that of diamond. It is currently the whisker with the highest hardness, the largest modulus, and the best heat resistance among whiskers. The crystal form is β-type, which has higher hardness, better comprehensive properties such as toughness and thermal conductivity, and is also one of the best reinforcing and toughening materials. It can significantly improve the toughness, flexural strength, hardness, wear resistance, and high temperature resistance, oxidation resistance, thermal conductivity, structural stability, thermal shock resistance, etc..

 

The silicon carbide whiskers treated with the coupling agent can be well and stably dispersed in the matrix, the whiskers are well infiltrated by the matrix, and the interface bonding strength is increased. Through this interface, the matrix and whiskers are connected as a whole. When the matrix is ​​subjected to external force, the stress can be uniformly transmitted through this interface and absorb a large amount of energy. On the one hand, when a crack appears in the matrix, the whiskers bridge the surface of the broken crack, which can hinder the further development of the crack; on the other hand, if the crack encounters silicon carbide powders, if it wants to develop further, the crystal must be destroyed or removed. Whiskers have high strength and high modulus, and it takes a lot of energy to destroy or pull out the whiskers, and when the crack bypasses the whiskers, it develops further and causes more microcracks. And because the whiskers have a relatively large L/D, more energy needs to be absorbed, thereby significantly increasing the strength and toughness of the EP matrix.